The present invention relates generally to the control of electric liquid heating apparatus such as electric water heaters. A relatively recent development in the control of electric water heaters is to replace their fairly simple electrical/mechanical heating control systems with more sophisticated and flexible electronic control systems to increase the overall functionality and performance of the water heaters. The present invention is directed to the provision in an electric water heater of an electronic control system which provides the water heater with further enhanced flexibility and performance including, for example, algorithms for protecting the water heater against dry firing and providing it with different user-selectable operational modes to enhance performance and reduce operational energy costs.
In a representatively illustrated embodiment thereof, the present invention provides a dual element electric water heater having incorporated therein, among other features, a specially designed multifunction electronic control system implementing various control algorithms including a dry fire protection algorithm, a user-selectable performance mode algorithm, and a user-selectable energy saver mode algorithm.